Why did the education and intelligence of advisors matter in Renaissance times in ways they had not earlier?

The Renaissance set the principle that "Man is the measure of all things". As a consequence, there was a growing interest in the development of humankind in all fields. In order for this to happen, improvements in education and intelligence were crucial. As a product of this growing importance of education, that Humanism was founded. Humanism is known as a stance that emphasizes the value of all human beings.